The chemical composition of various gemstones..."

Stephanie L. Kwolek

Stephanie Kwolek, the chemist who was credited with developing the Kevlar fiber used in bullet-resistant gear, conducts an experiment at her DuPont laboratory. (Courtesy of DuPont/Via AP) 

By Emily Langer June 20 

Stephanie L. Kwolek, a chemist credited with developing the ultra-strong Kevlar fiber used in bullet-resistant gear, an innovation that is estimated to have saved hundreds of lives since she created the polymer five decades ago, died June 18 at a hospice in Wilmington, Del. She was 90.

Rita Vasta, her executor and a former colleague at the DuPont chemical company, confirmed her death but declined to disclose the cause.

Miss Kwolek described her innovation as “a case of serendipity.” In the mid-1960s, halfway through her career as a DuPont chemist, she was tasked with developing a synthetic material that might offer a lighter, more fuel-efficient alternative to metal reinforcements in automobile tires.

In the course of her research, Miss Kwolek stumbled on a surprising compound — a liquid crystalline solution — that could be transformed into astoundingly strong fibers. Of them, the best known became Kevlar.

Five times as strong as steel, it proved immensely useful in a range of applications. Kevlar is used to make boats, airplanes and sporting equipment more sturdy. Woven into fabrics, it makes butcher’s gloves and lumberjack gear more protective. Ropes produced with Kevlar are strong enough to hold hulking ships in place and are easy for sailors to handle.

Miss Kwolek holds a spool of Kevlar, the ultra-strong fiber she helped develop, in this 2007 photo. (Jennifer Corbet/The News Journal via AP)

Most notably, it is used in the bullet- and stab-resistant vests and helmets worn by police officers, military personnel and other professionals working in dangerous environments. 

“Not in a thousand years did I think the discovery of this liquid solution would save thousands of lives,” Miss Kwolek told USA Today in 2003, amid the wars in Afghanistan and Iraq. “When I watch the war on TV, I take great pride in saying, ‘We at DuPont invented that.’ ”

Miss Kwolek was said to have encountered resistance during her research, in part because the polymer she created was so unusual.

“Ordinarily, when you have a polymer solution of a flexible polymer chain, it sort of reminds you of molasses,” Miss Kwolek told an interviewer for the Smithsonian Institution. “It may not be as thick but is generally of a transparent or translucent nature. With the polymer solution that I had, it was almost like water — and it was cloudy.”

To make fibers, polymer solutions were processed through the pores of a tool called a spinneret. The machine operator noted the cloudiness of Miss Kwolek’s substance and concluded that it indicated the presence of solid particles, which would have clogged the equipment.

In fact, the liquid crystalline solution represented a state of matter between conventional liquids and solids, with some of the properties of each, and it could be safely processed through the machine. In subsequent testing, the fibers proved exceptionally strong.

“The stiffness was absolutely spectacular,” Miss Kwolek told the New York Times. “That’s when I said, ‘Aha.’ I knew then and there it was an important discovery.”

Body armor has saved the lives or prevented the serious injury of more than 3,100 law enforcement officers, according to records maintained by the Kevlar Survivors’ Club, a joint initiative of DuPont and the International Association of Chiefs of Police.

Stephanie Louise Kwolek was born July 31, 1923, in New Kensington, Pa. She told interviewers that her father, who died when she was 10, had introduced her to the natural sciences by taking her foraging in the woods for insects and plants. Her mother introduced her to sewing, and in her youth Miss Kwolek hoped to become a fashion designer.

In 1946, she received a bachelor’s degree in chemistry from the Margaret Morrison Carnegie College, a women’s school associated with what is now Carnegie Mellon University in Pittsburgh. Lacking funds for medical school, she pursued employment at DuPont and developed an expertise in polymers.

She said she encountered challenges at a time when relatively few women worked in the advanced sciences.

“Although I’ve made many strides in my field, those were not enlightened times for the recognition and advancement of women in scientific research,” Miss Kwolek said in 1999, when s

he received a lifetime achievement award from the Lemelson-MIT Program.
“While I was doing work that was acknowledged to be on an equal level to that done by men, it took 15 years for me to get my first promotion, and that was far too long to wait,” she said.

Miss Kwolek credited her colleagues with making important contributions to the development of Kevlar and retired from DuPont in 1986. She was inducted into the National Inventors Hall of Fame in 1995 and received the National Medal of Technology in 1996, among other honors. She had no immediate survivors.
Miss Kwolek sometimes met or received phone calls from people who had worn her bullet-resistant fiber.

“Not long ago, I got to meet some troopers whose lives had been saved,” she once told the Philadelphia Inquirer. “They came with their wives, their children, their parents. It was a very moving occasion.”

Emily Langer is a reporter on The Washington Post’s obituaries desk. She has written about national and world leaders, celebrated figures in science and the arts, and heroes from all walks of life.

New Element Confirmed - Berkelium

 by Stephen Luntz

Photo credit: OTNL. We can't see the new element 117, but the berkelium used to make it is held between these tweezers

The periodic table has been extended, with the announcement of the confirmation of the yet to be named element 117.

In 2010 a US Russian collaboration announced they had produced atoms of an element with 117 protons, filling a gap that appeared when 118 was made four years earlier. However International Union of Pure and Applied Chemistry (IUPAC) insists on corroboration by two independent teams before it allows new elements to be added to the Periodic Table, although a temporary name of Ununseptium is in use until confirmation has been made. It has taken four years, but this appears to have finally arrived.

“Making element 117 is at the absolute boundary of what is possible right now,” says Professor David Hinde of the Australian National University, one of the authors of a paper published today in Physics Review Letters “That’s why it’s a triumph to create and identify even a few of these atoms.”

Hinde was part of a team at the GSI laboratory in Germany who fused calcium 48 and berkelium 249. This is not easy, because berkelium 249 is both hard to produce in substantial quantities and has a half life of 320 days. Less than half of any amount produced will still be around a year after it was made, which means transportation and purification can't wait. The resulting product, like all atoms heavier than lead, was unstable. By watching the alpha particles emitted the team concluded that these were the product of two decay chains, both originating with ²⁹⁴117, that is an atom with 117 protons and 177 neutrons. One of the chains included the isotopes ²⁷⁰Db and²⁶⁶Lr, the latter adding four neutrons to the previous highest isotope of lawrencium.

In general large atoms have shorter half lives, that is decay more quickly through radiation, as their masses become greater. However, what are know as islands of stability exist, and the authors believe the one hour half life of 270Db “marks an important step towards the observation of even more long-lived nuclei of superheavy elements located on an “island of stability.'”

The manufacturing process was hardly efficient. More than 1019 atoms of 48Ca, not a common isotope in its own right, were fired at the berkelium to produce just four atoms of 117. Nevertheless, Hinde says, “On the basis of this paper it is likely that element 117 will be accepted.” 

Element 117 is the most recent of six elements first announced by the Joint Institute for Nuclear Research in Russia. Of these 113, 115 and 118 remain unconfirmed, although claims have been made for the first two.

Such a small sample does not allow us to learn much about the chemistry of element 117. Ununseptium's position on the periodic table places it under the halogen gases such as fluorine and chlorine, but the strong capacity to capture electrons that makes these so reactive weakens as you go down the table, and in fact it is thought if one could ever produce enough to observe chemical interactions it would be more likely to lose electrons than gain them .

With a dozen new discoveries since he wrote The Elements, maybe it is time for Tom Lehrer to come out of retirement to add more lines to his song. Well we can hope.

Meanwhile Hinde has still greater dreams. “The big question is, how can we create elements 119 and 120?” To do this, however, a projectile heavier than 48Ca will need to be found. Hinde is working on identifying the best candidate.